Ballpoint pen



FIG. 1 is a perspective view of a ballpoint pen according to a first embodiment showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof, a bottom view being a mirror image; and,

FIG. 7 is a front view of usage.

The broken lines illustrate portions of the ballpoint pen and form no part of the claimed design. 

CLAIM The ornamental design for a ballpoint pen, as shown and described. 